From 650772d97efe98e578c18b8268b3bbed63ac4d18 Mon Sep 17 00:00:00 2001
From: melanie witt <melwittt@gmail.com>
Date: Thu, 18 Sep 2025 11:57:08 -0700
Subject: [PATCH] Add functional reproducer for bug 2125030

This reproduces the bug where an attempt to revert a resize from a
flavor with vTPM to a different flavor with vTPM results in the revert
failing and the instance going into ERROR state when storage is not
shared.

Because of the lack of test coverage of vTPM with non-shared storage,
this change also just adds a subclass to run all of the vTPM functional
tests with the test environment mocked to behave as though storage is
not shared between compute hosts.

A bug fix will follow these functional tests.

Related-Bug: #2125030

Change-Id: I49745a8ba78e1ea6a1b009bccab32a002cb6afb0
Signed-off-by: melanie witt <melwittt@gmail.com>
---
 nova/tests/functional/libvirt/test_vtpm.py | 73 ++++++++++++++++++++++
 1 file changed, 73 insertions(+)

diff --git a/nova/tests/functional/libvirt/test_vtpm.py b/nova/tests/functional/libvirt/test_vtpm.py
index 8c0fd9dbe1..e39c87288a 100644
--- a/nova/tests/functional/libvirt/test_vtpm.py
+++ b/nova/tests/functional/libvirt/test_vtpm.py
@@ -17,6 +17,7 @@ from unittest import mock
 
 from castellan.common.objects import passphrase
 from castellan.key_manager import key_manager
+import fixtures
 from oslo_log import log as logging
 from oslo_utils import uuidutils
 
@@ -239,6 +240,51 @@ class VTPMServersTest(base.ServersTestBase):
         # is still correct
         self.assertInstanceHasSecret(server)
 
+    def _test_resize_revert_server__vtpm_to_vtpm(self, extra_specs=None):
+        """Test behavior of revert when a vTPM is retained across a resize.
+
+        Other tests cover going from no vTPM => vTPM and vice versa.
+        """
+        for host in ('test_compute0', 'test_compute1'):
+            self.start_compute(host)
+
+        server = self._create_server_with_vtpm()
+
+        # Create a different flavor with a vTPM.
+        extra_specs = extra_specs or {
+            'hw:tpm_model': 'tpm-tis', 'hw:tpm_version': '1.2'}
+        flavor_id = self._create_flavor(extra_spec=extra_specs)
+
+        with mock.patch(
+            'nova.virt.libvirt.driver.LibvirtDriver'
+            '.migrate_disk_and_power_off', return_value='{}',
+        ):
+            server = self._resize_server(server, flavor_id=flavor_id)
+
+        # ensure our instance's system_metadata field and key manager inventory
+        # is updated to reflect the new vTPM requirement
+        self.assertInstanceHasSecret(server)
+
+        # revert the instance rather than confirming it, and ensure the secret
+        # is correctly cleaned up
+
+        with mock.patch(
+            'nova.virt.libvirt.driver.LibvirtDriver'
+            '.migrate_disk_and_power_off', return_value='{}',
+        ):
+            server = self._revert_resize(server)
+
+        # Should still have a secret because we had a vTPM before too.
+        self.assertInstanceHasSecret(server)
+
+    def test_resize_revert_server__vtpm_to_vtpm_same_config(self):
+        self._test_resize_revert_server__vtpm_to_vtpm()
+
+    def test_resize_revert_server__vtpm_to_vtpm_different_config(self):
+        extra_specs = {'hw:tpm_model': 'tpm-tis', 'hw:tpm_version': '2.0'}
+        self._test_resize_revert_server__vtpm_to_vtpm(
+            extra_specs=extra_specs)
+
     def test_resize_server__no_vtpm_to_vtpm(self):
         for host in ('test_compute0', 'test_compute1'):
             self.start_compute(host)
@@ -379,3 +425,30 @@ class VTPMServersTest(base.ServersTestBase):
         self.assertRaises(
             client.OpenStackApiException,
             self._shelve_server, server)
+
+
+class VTPMServersTestNonShared(VTPMServersTest):
+
+    def setUp(self):
+        super().setUp()
+        self.useFixture(fixtures.MockPatch(
+            'nova.compute.manager.ComputeManager._is_instance_storage_shared',
+            return_value=False))
+
+    # FIXME: Remove this entire method when
+    # https://bugs.launchpad.net/nova/+bug/2125030 is fixed.
+    def test_resize_revert_server__vtpm_to_vtpm_same_config(self):
+        ex = self.assertRaises(
+            client.OpenStackApiException,
+            self._test_resize_revert_server__vtpm_to_vtpm)
+        self.assertEqual(500, ex.response.status_code)
+
+    # FIXME: Remove this entire method when
+    # https://bugs.launchpad.net/nova/+bug/2125030 is fixed.
+    def test_resize_revert_server__vtpm_to_vtpm_different_config(self):
+        extra_specs = {'hw:tpm_model': 'tpm-tis', 'hw:tpm_version': '2.0'}
+        ex = self.assertRaises(
+            client.OpenStackApiException,
+            self._test_resize_revert_server__vtpm_to_vtpm,
+            extra_specs=extra_specs)
+        self.assertEqual(500, ex.response.status_code)